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WO2018133117A1 - Procédé et dispositif de commande pour recevoir une commande de faisceau dans un système mimo ainsi qu'unité radio et station de base - Google Patents

Procédé et dispositif de commande pour recevoir une commande de faisceau dans un système mimo ainsi qu'unité radio et station de base Download PDF

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Publication number
WO2018133117A1
WO2018133117A1 PCT/CN2017/072245 CN2017072245W WO2018133117A1 WO 2018133117 A1 WO2018133117 A1 WO 2018133117A1 CN 2017072245 W CN2017072245 W CN 2017072245W WO 2018133117 A1 WO2018133117 A1 WO 2018133117A1
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WO
WIPO (PCT)
Prior art keywords
gain
beamforming
target
controller
receiving beam
Prior art date
Application number
PCT/CN2017/072245
Other languages
English (en)
Inventor
Ming Li
Qingyu Miao
Jianfeng Wang
Virgile Garcia
Original Assignee
Telefonaktiebolaget Lm Ericsson (Publ)
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Telefonaktiebolaget Lm Ericsson (Publ) filed Critical Telefonaktiebolaget Lm Ericsson (Publ)
Priority to EP17892771.1A priority Critical patent/EP3563537A4/fr
Priority to US15/528,190 priority patent/US10382109B2/en
Priority to CN201780084223.2A priority patent/CN110235421B/zh
Priority to PCT/CN2017/072245 priority patent/WO2018133117A1/fr
Publication of WO2018133117A1 publication Critical patent/WO2018133117A1/fr

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G3/00—Gain control in amplifiers or frequency changers
    • H03G3/20—Automatic control
    • H03G3/30—Automatic control in amplifiers having semiconductor devices
    • H03G3/3036—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers
    • H03G3/3042—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers in modulators, frequency-changers, transmitters or power amplifiers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
    • H04B7/0636—Feedback format
    • H04B7/0639—Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
    • H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining
    • H04B7/0842—Weighted combining
    • H04B7/0848—Joint weighting
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/20—Control channels or signalling for resource management
    • H04W72/23—Control channels or signalling for resource management in the downlink direction of a wireless link, i.e. towards a terminal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/0001—Arrangements for dividing the transmission path
    • H04L5/0014—Three-dimensional division
    • H04L5/0023—Time-frequency-space
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
    • H04W52/04—Transmission power control [TPC]
    • H04W52/38—TPC being performed in particular situations
    • H04W52/42—TPC being performed in particular situations in systems with time, space, frequency or polarisation diversity

Definitions

  • Embodiments of the disclosure generally relate to wireless communication, and, more particularly, to method and controller for receiving beam control in multiple-input multiple-output (MIMO) system as well as radio unit and base station.
  • MIMO multiple-input multiple-output
  • Antenna array has been widely used in base stations. It generally comprises a set of individual antenna elements. In combination with MIMO technologies, the capacity of wireless channel may be increased without increasing the bandwidth and transmission power. Recently, massive MIMO (also known as large-scale antenna systems, very large MIMO, or hyper MIMO) has been developed. It makes use of a very large amount (e.g., hundreds or thousands) of service antennas that are operated fully coherently and adaptively. Thereby, the transmission and reception of signal energy can be focused into ever-smaller regions of space. This can bring huge improvements in throughput and energy efficiency, in particular when combined with simultaneous scheduling of a large number (e.g., tens or hundreds) of user terminals. Other benefits of massive MIMO include the extensive use of inexpensive low-power components, reduced latency, simplification of the media access control (MAC) layer, and robustness to interference and intentional jamming.
  • MAC media access control
  • Beamforming is a signal processing technique usually used in antenna array of MIMO system for directional signal transmission or reception. This may be achieved by combining antenna elements in a phased array in such a way that signals at particular angles experience constructive interference while others experience destructive interference. Beamforming can be used at both the transmitting and receiving ends in order to achieve spatial selectivity.
  • Analog beamforming implementations usually rely on a list of predefined beams (or codebooks) that can be selected to transmit/receive data streams. Beams can be set to form sectors, hotspots, or some spatial separations to allow user multiplexing. An antenna array spanning over two dimensions can perform both vertical and horizontal beam shaping. It is generally desirable to have a set of beams that can span the entire desired coverage area of the antenna array to avoid coverage holes for example.
  • analog beamforming is a method that applies weights (usually phase shifts) to the signals from the antenna elements and combines them in order to increase the antenna gain from a given direction. This combining is done in an analog domain, i.e. before the signal is converted to a digital stream. The result of such combining is treated as a digital stream by a digital front-end and a baseband processing unit.
  • FIG. 1 is a schematic architectural diagram showing a receiver having an analog beamforming combiner.
  • the receiver 100 may comprise a plurality of antenna elements 102 for receiving radio frequency (RF) signals.
  • RF radio frequency
  • the RF signals may be processed by respective RF processing units 104 such that the processed signals are provided to a beamforming combiner 106.
  • the beamforming combiner 106 may apply phase shifting to the processed signals by a plurality of phase shifters 108, and combine the signals after phase shifting, wherein the coefficients of the phase shifters are beamforming weights.
  • the combined signal may be converted to a digital signal by an analog-to-digital converter (ADC) 110, and may be further processed by a digital front-end 112.
  • ADC analog-to-digital converter
  • FIG. 1 is usually used in beam sweeping.
  • FIG. 2 is a schematic diagram of beam sweeping.
  • beam sweeping is a method used to scan the desired coverage area with beams in corresponding directions. This is needed when the location of a user is not known correctly, such as during random access procedure.
  • the transmitter tries all the beam directions available. For example, three beams with different beam indices (e.g., beam index 1, beam index 2 and beam index 3) are shown in FIG. 2 for illustration.
  • the beams used for covering respective directions are usually configured with a maximum gain.
  • the power levels and phases of signals received from the antenna array may change rapidly, and thus receiving beam control is performed in the receiver.
  • new problems arise, resulting in the performance degradation or very high cost of the receiver. Therefore, it would be desirable to provide an effective and low cost solution for receiving beam control.
  • One of the objects of the disclosure is to provide an effective and low cost solution for receiving beam control.
  • a method for receiving beam control in multiple-input multiple-output (MIMO) system comprises obtaining, from a power meter, a measured power of a signal, wherein the signal is generated by a beamforming combiner by combining multiple inputs from an antenna array, and represents a first receiving beam with a first gain and a first pointing direction.
  • the method further comprises judging whether to apply beam gain control based on the obtained power.
  • the method further comprises in response to a positive judgment result, determining a target gain.
  • the method further comprises converting the target gain to a target beamforming parameter.
  • the method further comprises providing the target beamforming parameter to the beamforming combiner, such that the first receiving beam is replaced by a second receiving beam with the target gain and the first pointing direction.
  • the step of judging comprises judging whether the obtained power is greater than or equal to a first threshold.
  • the step of determining comprises: when the obtained power is greater than or equal to the first threshold, determining a target gain which is smaller than the first gain.
  • the step of judging comprises judging whether the obtained power is smaller than a second threshold for a predetermined time length.
  • the step of determining comprises: when the obtained power is smaller than the second threshold for the predetermined time length, determining a target gain which is greater than the first gain.
  • the target beamforming parameter is represented by: a beam index comprising two levels of indices, wherein a first level of index corresponds to a pointing direction of a receiving beam, and a second level of index corresponds to a gain of the receiving beam; or one of a set of codebooks which contain weight vectors applied to the multiple inputs for generating receiving beams with multiple pointing directions and multiple gains in each pointing direction.
  • a controller for receiving beam control in multiple-input multiple-output (MIMO) system.
  • the controller comprises a processor and a memory.
  • the memory contains instructions executable by the processor, whereby the controller is operative to obtain, from a power meter, a measured power of a signal, wherein the signal is generated by a beamforming combiner by combining multiple inputs from an antenna array, and represents a first receiving beam with a first gain and a first pointing direction.
  • the instructions are executable by the processor, whereby the controller is further operative to judge whether to apply beam gain control based on the obtained power.
  • the instructions are executable by the processor, whereby the controller is further operative to, in response to a positive judgment result, determine a target gain.
  • the instructions are executable by the processor, whereby the controller is further operative to convert the target gain to a target beamforming parameter.
  • the instructions are executable by the processor, whereby the controller is further operative to provide the target beamforming parameter to the beamforming combiner, such that the first receiving beam is replaced by a second receiving beam with the target gain and the first pointing direction.
  • the instructions are executable by the processor, whereby the controller is further operative to report the beamforming parameter to a baseband processing unit.
  • a radio unit (RU) for a base station (BS) comprises an antenna array, a beamforming combiner coupled to the antenna array, a power meter coupled to the beamforming combiner, and the controller according to the above aspect.
  • the beamforming combiner is connected directly to the antenna array, or connected to the antenna array via a radio frequency (RF) processing unit.
  • RF radio frequency
  • the power meter is connected directly to the beamforming combiner, or connected to the beamforming combiner via an analog-to-digital converter.
  • the beamforming combiner has an amplitude adjustment capability.
  • the BS comprises the radio unit (RU) according to the above aspect.
  • the computer program comprises instructions which when executed by at least one processor, cause the at least one processor to perform the method according to the above aspect.
  • the computer readable storage medium comprises instructions which when executed by at least one processor, cause the at least one processor to perform the method according to the above aspect.
  • a controller for receiving beam control in multiple-input multiple-output (MIMO) system.
  • the controller comprises an obtaining module for obtaining, from a power meter, a measured power of a signal, wherein the signal is generated by a beamforming combiner by combining multiple inputs from an antenna array, and represents a first receiving beam with a first gain and a first pointing direction.
  • the controller further comprises a judgment module for judging whether to apply beam gain control based on the obtained power.
  • the controller further comprises a determination module for, in response to a positive judgment result, determining a target gain.
  • the controller further comprises a conversion module for converting the target gain to a target beamforming parameter.
  • the controller further comprises a provision module for providing the target beamforming parameter to the beamforming combiner, such that the first receiving beam is replaced by a second receiving beam with the target gain and the first pointing direction.
  • FIG. 1 is a schematic architectural diagram showing a receiver having an analog beamforming combiner
  • FIG. 2 is a schematic diagram of beam sweeping
  • FIG. 3 is a schematic architectural diagram of AGC function
  • FIG. 4 shows an existing AGC deployment in a receiver
  • FIG. 5 shows another existing AGC deployment in a receiver
  • FIG. 6 shows a glitch phenomenon in existing AGC deployments
  • FIG. 7 shows a system to which the principle of the disclosure is applicable
  • FIG. 8 is a flowchart illustrating a method for receiving beam control according to an embodiment of the disclosure.
  • FIGs. 9A and 9B are flowcharts for explaining the method of FIG. 8;
  • FIG. 10 is a schematic diagram showing a gain setting configuration according to an embodiment of the disclosure.
  • FIG. 11 shows beam indices according to an embodiment of the disclosure
  • FIGs. 12A and 12B are schematic diagrams of beam sweeping according to an embodiment of the disclosure.
  • FIG. 13 is a flowchart illustrating a method for receiving beam control according to another embodiment of the disclosure.
  • FIG. 14 is a block diagram showing a controller and a radio unit according to an embodiment of the disclosure.
  • FIG. 15 is a schematic architectural diagram showing a radio unit according to another embodiment of the disclosure.
  • FIGs. 16A and 16B show the comparison between the present disclosure and an existing AGC.
  • FIG. 17 is a block diagram showing a controller according to another embodiment of the disclosure.
  • FIG. 3 is a schematic architectural diagram of AGC function.
  • the RF front-end comprises a low noise amplifier (LNA) 304, a first filter 306, a first attenuator 308, a mixer 310, a second filter 312, a second attenuator 308’ and an ADC 318.
  • LNA low noise amplifier
  • the digital front-end comprises a digital power meter 320 and a digital compensation unit 324.
  • the devices in the dashed circle show an ‘AGC loop’ , which may include the digital power meter 320 for measuring the received power level, at least one trigger for triggering analog attenuation, at least one attenuator (e.g., 308 and 308’ ) , and the digital compensation unit 324 for keeping uniform receiver gain.
  • AGC loop may include the digital power meter 320 for measuring the received power level, at least one trigger for triggering analog attenuation, at least one attenuator (e.g., 308 and 308’ ) , and the digital compensation unit 324 for keeping uniform receiver gain.
  • FIG. 4 shows the first kind of AGC deployment in an analog beamforming receiver, which may be referred to as multi-branch AGC herein.
  • AGCs e.g., attenuators 408
  • Each receiver branch comprises an antenna element 402, an LNA 404, a first filter 406, an attenuator 408, a mixer 410 and a second filter 412.
  • the analog beamforming combiner 414 comprises four phase shifters 416, each of which is used for phase adjustments on a signal from a receiver branch.
  • An ADC 420 is used to convert the combined signal from the analog beamforming combiner 414 to a digital signal.
  • FIG. 5 shows the second kind of AGC deployment in an analog beamforming receiver, which may be referred to as common path AGC herein. As shown, one attenuator 522 is allocated in the common path after the analog beamforming combiner 514. The other devices are similar to those shown in FIG. 4.
  • the third kind of AGC deployment is a hybrid combination of multi-branch AGC and common path AGC.
  • the rapid change of the signal power level and phase will generate glitch during the transition through different gain/attenuation paths in the receiver, as shown in FIG. 6. Since the toggling is trimmed to give a period of time interval in ms order between each state change, it means that the AGC needs at least a period of time interval in ms order to re-stabilize the receiver gain, after the interference hits the receiver.
  • the glitch can affect the signal processing in the baseband in a negative way. Lots of glitches spread in time can cause the receiver efficiency to decrement rapidly and impact the throughput seriously. In the worst case, the receiving process would be temporarily interrupted or may even break down.
  • the glitch suppression method implemented in existing signal processing is simply to insert zero data instead of the samples affected by the glitch, but the glitch suppression also means more complicated timing alignment to catch glitch.
  • the drawback is that the power meter in the DFE after the beamforming combiner could not identify which separate branch is blocked by the interference. Thus, one power meter should be reserved for each branch. For hundreds of branches, it means that lots of hardware cost and occupied printed circuit board (PCB) size have to be maintained for AGC function. Thus, it is almost impossible to be implemented in a massive MIMO.
  • PCB printed circuit board
  • the dynamic range of AGC will be huge compared with single branch AGC.
  • the dynamic range of AGC is increasing with the number of antenna branches, based on principle of 10*log (N) , where N is the number of antenna branches.
  • AGC is a radio standalone operation which is excluded by baseband beamforming (BBBF) physical layer processing.
  • BBBF baseband beamforming
  • the present disclosure proposes a solution for receiving beam control. It may overcome at least one of the drawbacks mentioned above, or it may not overcome any one of the drawbacks mentioned above. Hereinafter, the solution will be described in detail with reference to FIGs. 7-17.
  • FIG. 7 shows a system to which the principle of the disclosure is applicable.
  • the system is a wireless communication system, and may comprise a base station (BS) 702 supporting communication related services in a coverage area (also referred to as a cell) .
  • BS 702 is also capable of communicating with a plurality of UEs, i.e. UEs 704-1 to 704-N within the coverage area.
  • the communications between BS 702 and UEs 704-1 to 704-N may employ any wireless communication standards such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and so on.
  • BS 702 comprises an antenna array. Based on the description given below, one skilled in the art will understand that the principle of the present disclosure may be applied to any BS with an antenna array.
  • BS 702 may conform to 3G standards, and comprise a NodeB and a radio network controller (RNC) .
  • the NodeB may comprise a remote radio unit (RRU) and a building baseband unit (BBU) .
  • BS 702 may be an evolved Node B (eNodeB) conforming to long term evolution (LTE) standards.
  • the eNodeB may comprise a RRU and a BBU.
  • BS 702 may be a gNB in a new radio (NR) system.
  • NR new radio
  • UEs 704-1 to 704-N may be referred to as, for example, devices, mobile stations, mobile units, subscriber stations, wireless terminals, terminals, or the like. Each one of them may be mobile or stationary, and may be, for example, a wireless handheld device such as a wireless phone, a computer with a wireless connection to a network, a wireless plug-in accessory, or the like.
  • FIG. 8 is a flowchart illustrating a method for receiving beam control according to an embodiment of the disclosure.
  • the method may be performed by for example the processor and the memory of a radio unit (e.g., RRU as described above) or a separate controller in the radio unit.
  • a measured power of a signal is obtained from a power meter, wherein the signal is generated by a beamforming combiner by combining multiple inputs from an antenna array, and represents a first receiving beam with a first gain and a first pointing direction.
  • the antenna array may comprise at least one set of antenna elements for receiving RF transmissions from a UE for example.
  • Each set of antenna elements may correspond to a receiving beam with a pointing direction and a gain in the pointing direction.
  • three sets of antenna elements may be used to generate three receiving beams which are separated from each other by 120 degrees.
  • each antenna element set may sequentially generate a series of receiving beams with different pointing directions such that each antenna element set can sweep one-third of the cell.
  • the multiple inputs from the antenna array may come from a set of antenna elements directly or indirectly via a RF processing unit.
  • the beamforming combiner may apply a beamforming weight vector (or a codebook) to the multiple inputs and combine them to generate the signal.
  • the beamforming combiner may comprise for example a plurality of phase shifters for applying phase shifts corresponding to the beamforming weight vector to the multiple inputs.
  • the beamforming combiner may further comprise an amplitude adjustment capability. To this end, it may comprise for example an attenuator.
  • the generated signal represents a receiving beam with a first gain and a first pointing direction.
  • the first gain used initially for the first pointing direction may be predefined for example according to the network operator’s configuration or a communication standard. As mentioned hereinbefore, to achieve the maximum coverage, the initially used first gain may be set to a maximum gain.
  • other receiving beams with different pointing directions may be sequentially generated to sweep the cell.
  • the signal generated by the beamforming combiner is an analog signal. It may come to the power meter directly from the beamforming combiner. In this case, the power meter is an analog power meter. Alternatively, the signal may come to the power meter from the beamforming combiner via an ADC which converts the signal to a digital one. In this case, the power meter is a digital power meter.
  • at least one power threshold may be predefined according to the network operator’s configuration or a communication standard, and the judgment may be made by comparing the obtained power with the at least one power threshold.
  • step 804 If it is judged at step 804 that beam gain control is not to be applied, the process may proceed to step 802 such that the signal’s power can be monitored. On the other hand, if it is judged at step 804 that beam gain control is to be applied, a target gain is determined at step 806. The target gain may be greater than or smaller than the first gain depending on the obtained power.
  • steps 804 and 806 may be implemented as steps 904 and 906 of FIG. 9A.
  • a first threshold may be a predefined value or a value defined in a communication standard. The first threshold may be different in different wireless communication systems or for different service cells or beam directions. If the judgment result at step 904 is negative (e.g., the obtained power is smaller than the first threshold) , the process may proceed to step 802. On the other hand, if the judgment result at step 904 is positive (e.g., the obtained power is greater than or equal to the first threshold) , it is determined at step 906 a target gain which is smaller than the first gain. In this way, when a high power signal (e.g., interference) occurs, the saturation of the receiver can be avoided.
  • a high power signal e.g., interference
  • steps 804 and 806 may be implemented as steps 904’ and 906’ of FIG. 9B.
  • the second threshold may be a predefined value or a value defined in a communication standard.
  • the second threshold may be different in different wireless communication systems or for different service cells or beam directions.
  • the predetermined time length may be a predefined by the network operator or defined in a communication standard.
  • the predetermined time length may be different in different wireless communication systems or for different service cells or beam directions.
  • step 904’ If the judgment result at step 904’ is negative (e.g., the obtained power is not smaller than the second threshold for a predetermined time length) , the process may proceed to step 802. On the other hand, if the judgment result at step 904’ is positive (e.g., the obtained power is smaller than the second threshold for a predetermined time length) , it is determined at step 906’ a target gain which is greater than the first gain. In this way, a receiving beam having too small gain for a period of time can be recovered to a receiving beam with a higher gain.
  • steps 804 and 806 may be implemented as a combination of the steps of FIGs. 9A and 9B. Firstly, step 904 is performed. If the judgment result at step 904 is positive, step 906 is performed, and then the process proceeds to step 808. On the other hand, if the judgment result at step 904 is negative, step 904’ is performed.
  • step 906’ is performed, and then the process proceeds to step 808. On the other hand, if the judgment result at step 904’ is negative, the process may proceed to step 802.
  • a suitable gain setting configuration for use by step 806 is shown in FIG. 10.
  • four gain control (GC) states are employed as an exemplary example.
  • the initial gain may correspond to GC state 0.
  • the target gain may be determined as GC state 3.
  • the target gain may be determined as GC state 1.
  • the number of the first or second thresholds may be more than one, and the first threshold may be identical to or different from the second threshold.
  • the gain settings shown in FIG. 10 are only used for explanation purpose, and there may be other suitable gain settings in other embodiments.
  • the target gain is converted to a target beamforming parameter.
  • the target beamforming parameter may be used by the beamforming combiner to generate a second receiving beam with the target gain and the first pointing direction.
  • Step 808 may be implemented by using any existing precoding techniques.
  • there are four beam gains which may be converted to four codebooks.
  • codebooks whose total number equals to the number of the pointing directions multiplied by four can be generated in advance. Accordingly, the target gain together with the first pointing direction may be mapped to a corresponding codebook.
  • the target beamforming parameter is represented by one of a set of codebooks, wherein the set of codebooks contain weight vectors applied to the multiple inputs for generating receiving beams with multiple pointing directions and multiple gains in each pointing direction.
  • the existing precoding architecture can be used to perform receiver gain control instead of AGC.
  • the target beamforming parameter may be any suitable parameter depending on the specific implementation of the beamforming combiner.
  • the target beamforming parameter may be represented by a beam index comprising two levels of indices, wherein a first level of index corresponds to a pointing direction of a receiving beam, and a second level of index corresponds to a gain of the receiving beam.
  • a table for mapping beam indices to codebooks may be set in the beamforming combiner. An exemplary example of such beam index is shown in FIG. 11.
  • the beam indices “2.1” , “2.2” , “2.3” and “2.4” each have two levels of indices, wherein the first level of index “2” corresponds to the pointing direction, and the second level of indices “1” , “2” , “3” or “4” correspond to the beam gain.
  • the target beamforming parameter is provided to the beamforming combiner, such that the first receiving beam is replaced by a second receiving beam with the target gain and the first pointing direction.
  • the beamforming combiner may use the target beamforming parameter (e.g., the codebook, the beam index, or the like) to generate the second receiving beam.
  • the analog beamforming architecture/process can be adaptive with various and dynamic blocking scenarios. For example, when a strong signal (e.g., interference) occurs, a beam with lower beamforming gain and similar pointing direction can replace the high beamforming gain beam so that the received signal power is lower. Thereby, the AGC processing can be eased or replaced, and thus the need for hardware for the traditional AGC can be avoided or reduced.
  • FIGs. 12A and 12B are schematic diagrams showing beam sweeping according to an embodiment of the disclosure.
  • the system is sweeping a sequence of predefined beams to cover an area.
  • a beam gain control is applied on a received signal, the beam used to cover that area will be replaced by a beam with another gain.
  • BS 1210 sequentially generates three beams with different pointing directions to sweep the cell.
  • the first receiving beam described above is used in beam sweeping to listen toward the first direction indicated by beam index 2.
  • the interference source may cause the signal’s power received by BS 1210 to be greater than or equal to the first threshold, and then a target gain smaller than the first gain is applied. As a result, a new beam with the target gain in the same direction replaces the original beam.
  • the beam indices of FIG. 11 may be applied to the scenarios shown in FIGs. 12A and 12B.
  • the new beam is a wider beam (with spatial beam-width increased) compared with the original beam.
  • the new wider transmitting beam may influence the operation of other neighboring base stations.
  • the use of the wider transmitting beam may be reported to other neighboring base stations, and may also be transparent to the users of these neighboring base stations.
  • the beam gain can be scaled without changing the antenna beam pattern ratio. That is, the new beam is still a narrow beam similar to the original beam.
  • the new narrow transmitting beam applies no influence to the operation of other neighboring base stations. Thus, the use of the new transmitting beam is not necessary to be reported to these neighboring base stations.
  • FIG. 13 is a flowchart illustrating a method for receiving beam control according to another embodiment of the disclosure.
  • the first receiving beam is used in beam-sweeping to listen toward the first pointing direction.
  • the method comprises steps 802-808 of FIG. 8 and steps 1302-1306. The details of steps 802-808 have been described above and thus are omitted here.
  • step 1302 it is checked whether the second receiving beam can replace the first receiving beam within current duration for listening toward the first pointing direction. If the check result at step 1302 is positive (e.g., the current remaining duration for listening toward the first pointing direction is longer than the beam switching time) , the target beamforming parameter is provided to the beamforming combiner within the current duration at step 1304.
  • the target beamforming parameter is provided to the beamforming combiner at step 1306 such that it is used as the initial beamforming parameter for a next duration of listening toward the first pointing direction. That is, when starting to listen toward the first pointing direction for the next time, the initially used first receiving beam is generated by applying the target beamforming parameter. Then, step 802 is performed to obtain the measured power of the signal representing the initially used first receiving beam. Then, step 804 is performed to judge whether to apply beam gain control. If beam gain control is not required, the process may proceed to step 802.
  • steps 806-810 are performed.
  • the following table may be maintained for indicating the list of beams to be used for next iteration of sweeping. It shows an exemplary case where the Beam #2 needs to apply a control gain.
  • the initially used first receiving beam is generated by applying the same beamforming parameter as that for the previous listening duration. In this case, the performing of steps 802-810 can ensure that suitable beam gain is applied.
  • the beamforming parameter may be reported to a baseband processing unit such that the baseband processing unit can know which beam or beam gain has actually been used for the reception and thus can correctly process the received signal. For example, a message with such information may then be communicated from the beamforming combiner, the separate controller or the digital front-end to the baseband processing unit.
  • FIG. 14 is a block diagram showing a controller and a radio unit (RU) according to an embodiment of the disclosure.
  • the controller 1410 comprises a processor 1412 and a memory 1414.
  • the memory 1414 contains instructions which may be executed by the processor 1412 to cause the controller 1410 to perform the method steps described above with reference to FIGs. 8-13.
  • the RU 1400 comprises an antenna array 1402, a beamforming combiner 1404, a power meter 1406 and the controller 1410.
  • the antenna array 1402 may comprise at least one set of antenna elements for receiving RF transmissions.
  • the beamforming combiner 1404 is coupled to the antenna array 1402. It may apply a beamforming weight vector (or a codebook) to the multiple inputs from the antenna array 1402 and combine them to generate the signal which may represent a first receiving beam with a first gain and a first pointing direction.
  • the power meter 1406 is coupled to the beamforming combiner 1404, and may measure the signal’s power.
  • FIG. 15 is a schematic architectural diagram showing a radio unit according to another embodiment of the disclosure.
  • the RU 1500 comprises an antenna array 1502, a plurality of RF processing units 1504 each of which is connected to an antenna element of the antenna array 1502, a beamforming combiner 1506, an ADC 1508, a power meter 1510, a controller 1512 and a digital compensation unit 1514.
  • This embodiment is similar to that of FIG. 14 except that this embodiment further comprises the RF processing units 1504, the ADC 1508 and the digital compensation unit 1514.
  • the RF processing units 1504 are connected between the antenna array 1502 and the beamforming combiner 1506, and may perform RF-to-baseband processing. It may be implemented similar to existing RF processing units such as shown in FIGs. 4 and 5.
  • the ADC 1508 is connected between the beamforming combiner 1506 and the power meter 1510, and is disposed in a DFE.
  • the ADC 1508 may convert the signal from the beamforming combiner 1506 to a digital one.
  • the digital compensation unit 1514 may provide relative digital power compensation to keep uniform receiver gain, and may be implemented similar to any existing AGC.
  • an RF processing unit may be connected between the beamforming combiner and the ADC.
  • an RF processing unit may be connected after the power meter.
  • the power meter may be connected between the beamforming combiner and the ADC, and thus is an analog power meter.
  • FIGs. 16A and 16B show the comparison between the present disclosure and an existing AGC. They demonstrate a simplified mapping between beam index and receiver gain/dynamic range, wherein FIG. 16A corresponds to the existing AGC and FIG. 16B corresponds to the beam gain control of the present disclosure.
  • beam #2 is taken as example for illustration, wherein Gbeam#2 represents a gain of Beam #2, Gbeam#2.4 represents a gain of Beam#2.4, and Greceiver represents a gain of the receiver.
  • UL gain For overall uplink (UL) gain, it is the sum of Gbeam and Greceiver to bring enough UL signal noise ratio (SNR) for digital and baseband processing.
  • SNR signal noise ratio
  • FIG. 16A For the existing AGC, the sum of (Gbeam + Greceiver with AGC) is shown in FIG. 16A. It can be seen that Gbeam#2 is fixed, and Greceiver is dynamically changed.
  • FIG. 16B the sum of (different Gbeam + Greceiver) is shown in FIG. 16B. it can be seen that Gbeam is dynamically changed from Gbeam#2 to Gbeam#2.4 to mitigate Greceiver dynamic range shown in FIG. 16A, all or partly, with a good defined beam gain control. In this way, the glitch problem caused by the traditional AGC adjustment can be fully avoided to support the possible rapid beamforming gain adjustments in analog beamforming without cost and complexity increasing.
  • FIG. 17 is a block diagram showing a controller according to another embodiment of the disclosure.
  • the controller 1700 comprises an obtaining module 1702, a judgment module 1704, a determination module 1706, a conversion module 1708 and a provision module 1710.
  • the obtaining module 1702 may be configured to perform step 802.
  • the judgment module 1704 may be configured to perform steps 804, 904 or 904’ .
  • the determination module 1706 may be configured to perform steps 806, 906 or 906’ .
  • the conversion module 1708 may be configured to perform step 808.
  • the provision module 1710 may be configured to perform step 810 or steps 1302-1306.
  • the controller 1700 may further comprise a reporting module configured to report the beamforming parameter to a baseband processing unit.
  • the various exemplary embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof.
  • some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto.
  • firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto.
  • While various aspects of the exemplary embodiments of this disclosure may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.
  • the exemplary embodiments of the disclosure may be practiced in various components such as integrated circuit chips and modules. It should thus be appreciated that the exemplary embodiments of this disclosure may be realized in an apparatus that is embodied as an integrated circuit, where the integrated circuit may comprise circuitry (as well as possibly firmware) for embodying at least one or more of a data processor, a digital signal processor, baseband circuitry and radio frequency circuitry that are configurable so as to operate in accordance with the exemplary embodiments of this disclosure.
  • exemplary embodiments of the disclosure may be embodied in computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices.
  • program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device.
  • the computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, RAM, etc.
  • the function of the program modules may be combined or distributed as desired in various embodiments.
  • the function may be embodied in whole or in part in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA) , and the like.
  • FPGA field programmable gate arrays

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Abstract

L'invention concerne un procédé et un dispositif de commande pour recevoir une commande de faisceau dans un système MIMO. Selon un mode de réalisation, une puissance mesurée d'un signal est obtenue à partir d'un capteur de puissance. Le signal est produit par un combineur de formation de faisceau en combinant de multiples entrées provenant d'un réseau d'antennes, et représente un premier faisceau de réception avec un premier gain et une première direction d'orientation. Il est jugé s'il faut appliquer ou non une commande de gain de faisceau en fonction de la puissance obtenue. En réponse à un résultat de jugement positif, un gain cible est déterminé. Le gain cible est converti en un paramètre de formation de faisceau cible. Le paramètre de formation de faisceau cible est fourni au combineur de formation de faisceau, de sorte que le premier faisceau de réception soit remplacé par un deuxième faisceau de réception avec le gain cible et la première direction d'orientation. L'invention concerne également une unité radio comprenant le dispositif de commande et une station de base comprenant l'unité radio.
PCT/CN2017/072245 2017-01-23 2017-01-23 Procédé et dispositif de commande pour recevoir une commande de faisceau dans un système mimo ainsi qu'unité radio et station de base WO2018133117A1 (fr)

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EP17892771.1A EP3563537A4 (fr) 2017-01-23 2017-01-23 Procédé et dispositif de commande pour recevoir une commande de faisceau dans un système mimo ainsi qu'unité radio et station de base
US15/528,190 US10382109B2 (en) 2017-01-23 2017-01-23 Method and controller for receiving beam control in MIMO system as well as radio unit and base station
CN201780084223.2A CN110235421B (zh) 2017-01-23 2017-01-23 用于mimo系统中的接收波束控制的方法和控制器以及无线电单元和基站
PCT/CN2017/072245 WO2018133117A1 (fr) 2017-01-23 2017-01-23 Procédé et dispositif de commande pour recevoir une commande de faisceau dans un système mimo ainsi qu'unité radio et station de base

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PCT/CN2017/072245 WO2018133117A1 (fr) 2017-01-23 2017-01-23 Procédé et dispositif de commande pour recevoir une commande de faisceau dans un système mimo ainsi qu'unité radio et station de base

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020032848A1 (fr) * 2018-08-07 2020-02-13 Telefonaktiebolaget Lm Ericsson (Publ) Gestion d'interférence de bs à bs dans des réseaux d'accès radioélectrique
WO2020221438A1 (fr) * 2019-04-30 2020-11-05 Telefonaktiebolaget Lm Ericsson (Publ) Systèmes et procédés de sélection de faisceau

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109644026B (zh) * 2016-09-06 2022-03-08 瑞典爱立信有限公司 用于确定波束成形信息的方法和装置
US11564182B2 (en) * 2018-10-09 2023-01-24 Telefonaktiebolaget Lm Ericsson (Publ) Method and apparatus for power control
US11483722B2 (en) 2019-09-17 2022-10-25 Corning Research & Development Corporation Multi-band remote unit in a wireless communications system (WCS)
CN112889345B (zh) * 2019-09-30 2022-08-09 华为技术有限公司 用于多输入多输出mimo通信的装置及系统
WO2021097638A1 (fr) * 2019-11-19 2021-05-27 华为技术有限公司 Procédé et appareil de commande d'antennes en réseau
EP4032195B1 (fr) * 2019-12-20 2025-09-24 Telefonaktiebolaget LM Ericsson (publ) Procédé et appareil de communication à antennes multiples
CN116193543A (zh) * 2021-11-26 2023-05-30 中兴通讯股份有限公司 节能控制方法及其装置、存储介质、程序产品

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080273636A1 (en) * 2007-05-04 2008-11-06 Mingrui Zhu Automatic gain control circuit for mimo ofdm receiver
US20090304128A1 (en) * 2008-06-08 2009-12-10 Seiichi Izumi Packet Detection Apparatus and Method, Wireless Communication Apparatus and Method, and Computer Program
US20100159854A1 (en) * 2008-12-19 2010-06-24 Electronics And Telecommunications Research Institute Method and apparatus for adaptively controlling received power of multi-antenna radio channel measurement equipment
CN103098404A (zh) * 2010-06-07 2013-05-08 熵通信有限公司 利用接收器和天线阵列元件实时多路复用的方法和设备
CN104702308A (zh) * 2014-12-12 2015-06-10 庄昆杰 一种微型化结构MiMo射频前端组件
US20160043792A1 (en) 2014-08-08 2016-02-11 Samsung Electronics Co., Ltd. Apparatus and method for adjusting receive beam gain in a wireless communication system
US20160066279A1 (en) 2014-08-29 2016-03-03 Samsung Electronics Co., Ltd. Method and Apparatus for Adjusting Beam Width in Wireless Communication System

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6115409A (en) * 1999-06-21 2000-09-05 Envoy Networks, Inc. Integrated adaptive spatial-temporal system for controlling narrowband and wideband sources of interferences in spread spectrum CDMA receivers
JP3593969B2 (ja) * 2000-10-25 2004-11-24 日本電気株式会社 送信アンテナ指向性制御装置及びその方法
KR100456454B1 (ko) * 2002-10-07 2004-11-09 한국전자통신연구원 무선통신에서의 배열 안테나 시스템
US7277730B2 (en) * 2002-12-26 2007-10-02 Nokia Corporation Method of allocating radio resources in telecommunication system, and telecommunication system
US7302238B2 (en) * 2003-04-25 2007-11-27 Samsung Electronics Co., Ltd. Transmit diversity system, method and computer program product
US7645236B2 (en) * 2005-06-28 2010-01-12 Siemens Medical Solutions Usa, Inc. Ultrasound imaging system having motion adaptive gain
CA2542445A1 (fr) * 2006-04-07 2007-10-07 Tenxc Wireless Inc. Systeme adaptatif multifaisceau
WO2008118474A2 (fr) * 2007-03-26 2008-10-02 Sibeam, Inc. Développements apportés à un procédé de déplacement de faisceau adaptatif
US7714783B2 (en) * 2007-08-02 2010-05-11 Samsung Electronics Co., Ltd. Method and system for analog beamforming in wireless communications
US8442457B2 (en) * 2009-09-08 2013-05-14 Google Inc. System and method for adaptive beamforming for specific absorption rate control
US8358239B2 (en) * 2010-04-01 2013-01-22 Massachusetts Institute Of Technology Iterative clutter calibration with phased array antennas
WO2014116068A1 (fr) * 2013-01-25 2014-07-31 Samsung Electronics Co., Ltd. Procédé et appareil de régulation du gain dans un système de communications prenant en charge un schéma de conformation de faisceaux
CN104937971B (zh) * 2013-11-29 2019-05-28 华为终端有限公司 波束预编码方式上报方法、调度方法及设备
KR102314602B1 (ko) * 2015-04-23 2021-10-19 한국전자통신연구원 안테나 장치 및 그 빔포밍 방법
US10382148B2 (en) * 2015-05-19 2019-08-13 Ets-Lindgren, Inc. System and method for calibration, monitoring and control of an anechoic boundary array RF environment simulator
US10320093B2 (en) * 2016-08-31 2019-06-11 Anokiwave, Inc. Phased array control circuit

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080273636A1 (en) * 2007-05-04 2008-11-06 Mingrui Zhu Automatic gain control circuit for mimo ofdm receiver
US20090304128A1 (en) * 2008-06-08 2009-12-10 Seiichi Izumi Packet Detection Apparatus and Method, Wireless Communication Apparatus and Method, and Computer Program
US20100159854A1 (en) * 2008-12-19 2010-06-24 Electronics And Telecommunications Research Institute Method and apparatus for adaptively controlling received power of multi-antenna radio channel measurement equipment
CN103098404A (zh) * 2010-06-07 2013-05-08 熵通信有限公司 利用接收器和天线阵列元件实时多路复用的方法和设备
US20160043792A1 (en) 2014-08-08 2016-02-11 Samsung Electronics Co., Ltd. Apparatus and method for adjusting receive beam gain in a wireless communication system
US20160066279A1 (en) 2014-08-29 2016-03-03 Samsung Electronics Co., Ltd. Method and Apparatus for Adjusting Beam Width in Wireless Communication System
CN104702308A (zh) * 2014-12-12 2015-06-10 庄昆杰 一种微型化结构MiMo射频前端组件

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3563537A4

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020032848A1 (fr) * 2018-08-07 2020-02-13 Telefonaktiebolaget Lm Ericsson (Publ) Gestion d'interférence de bs à bs dans des réseaux d'accès radioélectrique
US11425577B2 (en) 2018-08-07 2022-08-23 Telefonaktiebolaget Lm Ericsson (Publ) Handling of BS-to-BS interference in radio access networks
WO2020221438A1 (fr) * 2019-04-30 2020-11-05 Telefonaktiebolaget Lm Ericsson (Publ) Systèmes et procédés de sélection de faisceau

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US10382109B2 (en) 2019-08-13
CN110235421A (zh) 2019-09-13
EP3563537A1 (fr) 2019-11-06
EP3563537A4 (fr) 2019-12-04
CN110235421B (zh) 2022-04-29

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